To generate power from sunlight, the most common approaches are either photovoltaic (PV), where sunlight directly excites electron-hole pairs, or solar thermal, where sunlight drives a mechanical heat engine. However, since power generation using PVs is intermittent and typically only utilizes a portion of the solar spectrum efficiently, and the solar thermal approach is best suited for utility-scale power plants, there is an imminent need for hybrid technologies. Solar thermal photovoltaic technologies, that convert solar radiation to heat and then to electricity, promise to leverage the benefits of both approaches. However, the need for high operating temperatures of the devices makes spectral control and the efficient collection of sunlight particularly challenging, limiting prior experimental demonstrations to solar-to-electrical conversion efficiencies around 1% or below.